Control circuit



R. E. KOONTZ April 4, 1939.

CONTROL C IHCUIT Fi led Sept. 25, 1937 2 Sheets-Sheet l INVENTOR. fi/CHARD E Koo/v72 ML 5 AT 'I ORNEYS.

R. E. KOONTZ CONTROL CIRCUIT April 4, 1939.

iled Sept. 25, 1957 2 Sheets-Sheet 2 z Mm M a fiww Hu MWNII mm mm J E Wm W VS mm QQ A TTORNEYS Patented Apr. 4, 1939 UNITED STATES PATENTOFFICE CONTRO L CIRCUIT Application September 25, 1937, Serial No.165,621

2 Claims.

This invention relates to control circuits for wire-drawing and similarmachines. An object of the invention is to provide simple and efiectivecontrol means for a machine operating in 5 successive stages, or made upof a series of units.

It is particularly desirable to be able to operate the unitsindividually, for example in threading the wire through the machine,while retaining a single control for ordinary use and to include in themotor circuits, arranged to permit this, individual adjustments forindependently varying the speed of the several motors driving the units.It is also desirable to arrange the circuit so that actuation of any oneof a plurality of safety devices will stop the entire machine.

The above and other objects and novel fea-- tures of the invention willbe apparent from the following description of the illustrativeembodiment shown in the accompanying drawings, in which:

Figure 1 is a side elevation of a machine of the type to be controlledby the novel control circuit; and

Figure 2 is a wiring diagram of the novel control circuit.

A machine of the type to be controlled by applicants novel controlcircuit is described below. This machine is claimed and more completelydescribed in the copending application of Robert C. Pierce, Serial No.150,476, filed June 26, 1937.

Figure 1 illustrates a wire drawing machine in which the wire is passedsuccessively through three dies. Such a machine as is illustrated iscalled a three pass machine and may be considered as consisting of threeunits mounted on a frame iii which may be built up of standardstructural steel shapes and plates welded together to form suitablesupports for the various mechanisms.

The frame 90 is arranged to provide a lower platform l2 upon which aremounted three motors Hi, 16 and Hi, the motor H1 in this particularmachine being a constant speed alternating ourrent motor, e. g., asquirrel cage induction motor; and the motors l6 and !8 being variablespeed alternating current motors, preferably phase wound rotor inductionmotors.

These motors drive three capstan wheels 22, 24 and 25 arranged in ahorizontal line along the machine and in a vertical plane. The drivingmeans between the motors and capstans consists of belts 28 drivingpulleys 30 journalled in blocks on a second platform 32 provided by theframe iii, the pulleys 30 being connected by suitable gearing to drivethe capstan wheels at the desired speed.

In the first two units of the illustrated machine this gearing comprisespinions 34 mounted on the same shafts with the pulleys 30, driving gears36 on layshaft 38 carrying additional pinions 40 which drive large gears42 secured on shafts 44 on which the capstan wheels are mounted. Theshafts 44 are journalled in blocks 46 attached to the platform 32.

In the third unit, due to the fact that each capstan must run at anaverage higher speed than the preceding one, one set of gears e. g. gear38, its layshaft 38 and pinion 40, is eliminated and the pinion 34drives the large gear 42 directly.

Each of the capstans has associated therewith a die holder 48, 56 or 52respectively, each containing a die (not shown) positioned with itscenter in the line of a vertical tangent to the left hand side of theperiphery of the respective capstan. The 'capstans rotatecounterclockwise so as to draw the wire vertically downward through thedies.

Wire is fed to the die in holder 48 from a guide sheave 54 rotatablymounted on a fixed bracket 56 attached to the top of the frame It) insuch a position that the wire leaves the sheaves 54 in line with the dieand capstan periphery. Suitable means (not shown) for supplying wire tothe guide sheave are provided.

Wire passes from the capstan 22 to the capstan 24 and from the capstan24 to the capstan 26 over guide sheaves 56 and 58 respectively rotatablymounted on slides 60 and 62 vertically movable on guides 64 and 66.These guides are shown as formed of two cylindrical rods 68 secured attheir lower ends in brackets 10 bolted to the top of the frame Hi. Theslides 60 and 62 are disposed between the pairs of rods and are formedwith lugs having oppositely outwardly directed semi-circular groovesfitting around the rods.

In order to tension the wire as it enters the die, sprocket chains I4are secured to the top of each slide. These chains pass over weightedsprockets as described and claimed in the copending application ofRobert C. Pierce, Serial No. 68,856 filed March 14, 1936.

Another guide pulley 85, swingably mounted on a slide 86, slidable in aguide 88, is positioned to receive wire from the capstan 26 and feed itunder tension to a windup reel (not shown). The movements of this slidemay be utilized to control the speed of the windup reel.

An important feature of this machine resides in the means forcontrolling the speed of the motors I6 and I8 so as to maintain the wiretight and pass it on through each unit as rapidly as it leaves thepreceding one while at the same time giving it a constant back pull.

To accomplish this the two variable speed motors I6 and I8 arerespectively provided with rheostats and 92 of any standard type showndiagrammatically in Figure 2 as each comprising in the case of threephase motor, three sets of contact points 94 arranged in arc of a commoncircle and tapping successive portions of three resistances 96. To oneend of each of the resistances is connected one phase lead of the woundrotor of the respective motor, and a three armed movable contactor 94pivoted on the center of the above mentioned common circle serves toconnect the phase leads in Y, and upon rotation to simultaneouslyintroduce or take out resistances 96 in each phase. The mechanism forrotating the contactor (not shown herein) is claimed in the firstabove-mentioned Pierce application.

It will be understood that in the actual rheostat the contacts are soclosely arranged or the contactor arms are so broad that they engage thenext contact before disengaging the first one so that the rotor circuitsare closed at all times.

The rheostats 90 and 92 with their associated operating levers I00 areshown in Fig. 1 mounted on the upper part of the machine frame just tothe left of the guides 64 and 66 respectively.

A switch box I84 is mounted on the machine in any desired position, thisbox containing for a three pass machine, four automatic switches threeof which, designated respectively I86, I88, and I90, are single throwthree pole switches operated respectively by solenoids I92, I94 and I96,and the fourth of which is a single throw 4 pole switch I98 operated bya solenoid 200.

Adjacent the first unit of the machine are positioned a jog button 202for turning over the first unit separately, a start button 204 forstarting the whole machine together and a stop button 206 for stoppingthe whole machine. Jog buttons 208 and M0 are provided adjacent the twosucceeding units for turning them over individually.

A three phase power line 2I2 is conducted to the switch box I84 thethree wires of which may be designated I, 2 and 3. Each of these wiresis divided three ways and connected to the contacts of the switches I86,I88 and I90.

The power lines from the motors I4, I6 and I8 are connected respectivelyto the poles of the switches I86, I88 and I90. Thus closing any of theseswitches starts the corresponding motor. The solenoids of all theswitches have one terminal connected to phase wire I. The otherterminals are connected to leads 2I4, 2I6 and 2I8 each of which divideinto parallel circuits 2 I9 and 220, 222 and 224, 226 and 228respectively. Circuits 2 I9, 222 and 226 are respectively connected toone contact of the push buttons 202, 208, and 2I0. The other contacts ofthese push buttons are connected to lead 2 of the power line by a wire229 which also connects all four contacts of the switch I98 to lead 2.Circuits 229, 224 and 228 are each connected to a pole of the switchI98.

Solenoid 200 is also connected to phase lead I and its other terminal isconnected to a line 230 which extends to one contact of the start button204 the other contact being connected through wire 229 to lead 2.shunted around the start button 204 is a circuit 232 containing the stopbutton 206 and a series of limit switches 234. The circuit 232 isconnected to the remaining pole of the switch I98. It should be notedthat the jog and start buttons are make switches and the stop button andlimit switches are break switches, the limit switches are placed in manypositions around the machine and arranged to be operated by manycontingencies such as wire breakage, tangling, etc.

The operation of the circuit is as follows. In threading the machine itis desirable to operate any one of the motors I4, I6 or I8 individually.This is done by pushing and holding the respective jog button 202, 208or 2I0 positioned by that motor to energize the solenoid I92, I94 or I96to close the respective switch I86, I88, I90. For example, upon pushingand holding the jog button 202 a circuit is closed from line I of thecircuit wires 2I2, through solenoid I92 of switch I86 (thereby causingthe closing of the switch), through lines 2M and 2I9 and jog button 202,to line 229 and thence to line 2 of circuit wires 212. So long as thebutton 202 is held, the switch I86 remains closed and the motor I4 runs.Upon releasing the button the motor stops. Similarly, the closing of jogbutton 208 closes the switch I88 to cause the motor I6 to run, and theclosing of jog button 2I0 closes the switch I90 to cause the motor I8 torun. In threading the wire through each first two units of the machine,the motor I4 or I6 is run long enough to draw through the die of thatunit enough Wire to thread through the succeeding unit or units of themachine. With the machine threaded, the start button 204 is pushedenergizing the solenoid 200 and closing the switch I98. This in turnenergizes all of the solenoids I92, I94 and I96 and closes all theswitches I86, I88 and I90 to start all the motors simultaneously.

The circuit 232 is closed by the switch I98 to constitute a holdingcircuit for that switch so that the motors continue to run upon releaseof the start button. But upon opening circuit 232 by pushing the stopbutton 206 or any of the limit switches all the motors stop.

While one particular arrangement of wiring has been described in detail,it is not my intention to limit the scope of the invention to that exactarrangement, or otherwise than by the terms of the appended claims.

I claim:

1. A control circuit for a plurality of variable speed alternatingcurrent motors comprising independently adjustable rheostats connectedto and controlling the speed of said motors respectively, power lines,switches for connecting said motors with their rheostats individually tothe power lines, a solenoid for operating each switch, amanually-operable device corresponding to each motor for closing acircuit between two of the power lines through the solenoid of theswitch for that motor for individually energizing said motors, amanually-operable multiple switch for closing circuits between two ofthe power lines through all of said solenoids to start all of saidmotors, a holding circuit closed by actuation of said multiple switchfor holding said multiple switch in closed position, and means forbreaking the holding circuit and thereby opening the multiple switch andbreaking all of the solenoid circuits.

2. A control circuit for a plurality of motors comprising power lines,switches for connecting solenoids to start all of said motors, a holdingcircuit closed by actuation of said multiple switch for holding saidmultiple switch in closed position, and means for breaking the holdingcircuit and thereby opening the multiple switch 5 and breaking all ofthe solenoid circuits.

RICHARD E. KOONTZ.

